A fan filter unit (FFU) is a leading-edge FFU unit designed to provide filtered laminar airflow over a specific area. The unit integrates a high-efficiency fan together with a HEPA filter. The FFU draws in contaminated air from top of the module and exhausts filtered clean air vertically from class 100 to class 100000 clean rooms. ISO-Class 5 (as per ISO Standard 14644-1 )